Eight suspected North Korean bodies have washed ashore from a wrecked "ghost ship" in central Japan.

Key points:

Badges depicting North Korean founder Kim Il-sung and former leader Kim Jong-il were also recovered

Earlier this month the Japanese Coastguard reported that 104 "ghost ships" were detected last year

Previous vessels which have arrived have had Korean markings, but this one did not

Local police told the ABC the badly decomposing bodies were found with a badge of North Korean founder Kim Il-sung and former leader Kim Jong-il.

Police found the wooden boat last week and discovered one body, but bad weather prevented them from getting a closer look.

"We went back on [Monday] and this time we found seven more bodies," Kanazawa West senior police official Hiroshi Abe said.

"We are trying to find their identities and if we cannot find the owner of the ship, we will give it to the local government."

The skeletal remains were found with a cigarette box with Korean characters — but authorities are yet to formally confirm the boat or the corpses' origins.

Earlier this month the Japanese Coastguard reported that 104 of these wooden vessels were detected last year — a significant increase from the 66 confirmed the year before.

Previous vessels which have arrived have had Korean markings, but this most recent one did not.

Experts believe the people on these ships were likely fishermen on an ill-fated, but government-mandated, search for bigger catches.

But their old and poorly equipped vessels are prone to mechanical and other problems, including running out of fuel, and there are few ways for them to call for rescue.

A severe shortage of food and foreign currency — as international sanctions over Pyongyang's nuclear and missile ambitions bite — are contributing to a wave of poorly equipped North Korean fishing boats washing up in Japanese waters, pundits say.